Oil still tube



Aug. 28, 1934.

S. DAYSON OIL STILL TUBE Filed July 22, 1929 Patented Aug. 28, 1934 OIL STILL TUBE Sylvester Dayson, El Dorado, Ark. Application July 22, 1929, Serial No. 380,150

- 1 Claim.

The tubes of oil stills at their ends connected with the return bends or headers in about a month undergo such deterioration or wear from corrosion and erosion due to the action of the 5 oil that they must be replaced. This is a serious matter because the still must be shut down to cut out and replace the worn tubes. In an oil tube still having a capacity of two thousand barrels per day the loss from the shut down will be about a thousand dollars per day. To this must be added the cost of labor and material which amounts to about a hundred dollars per tube. Then there is danger, if a weakened tube is not removed in time, it will burst and thus cause fire and other damage. The object of my invention is to remedy this serious situation and to do so by means as simple and inexpensive as possible.

My invention conists in whatever is described by or is included within the terms or scope of the 20 appended claim.

In the drawing:-

Fig. 1 is a detail view in section showing a return bend or header and tubes connected therewith;

Fig. 2 is an end view thereof.

The tubes in an oil still are arranged in banks, some connected in parallel and some in series, the tubes of a bank being parallel and the ends of adjacent tubes being connected by return bends or headers. I have observed that wear of the tube interior occurs at the ends, adjacent the header, and it is due to corrosion from chemical action of the oil constituents and erosion, both corrosion and erosion being due to the turbulence,

or agitation of the oil promoted by violent change of direction in passing between the tubes and headers. Based on this knowledge, I conceived the idea that this wear problem would be solved by placing in that portion of each tube where wear occurs, a surface that would resist the corroding and eroding effects of oil. Such a surface on the tube interior, I provide by means of a sleeve or bushing of some metal, or alloy, having properties to resist corrosion and erosion, which the tube itself lacks, and of which the tube in itself cannot be commercially made because of cost of such metals or alloys, and which because of mechanical difficulties cannot be practical. I have tried various alloys, and what I now consider most satisfactory, is the socalled stainless steel. Tests after five months use have shown no alteration whatever of the surfaces exposed to the action of oil in the still. But of course I do not limit myself to the use of only that alloy.

Describing in detail the illustrative, typical embodiment shown in the drawing, there are end portions of two horizontal still tubes, 10, shown, and a header, 11, in holes in the end wall of which the tube ends are secured. These tubes, 10, are of the usual metal, which, as I have said is exposed to the wearing or deteriorating action of the oil. Within the open end of each tube, 10, is a sleeve or bushing, 12, of the desired metal or alloy having the properties to resist or withstand the chemical and mechanical action of the oil in flowing between the tube ends and the header. Said sleeve has a length to extend from the open end of the tube in the header over the distance in which the baneful effects of the oil are caused. Its length is comparatively short. To accommodate such sleeve the interior of the tube is reamed out an extent corresponding with the external diameter of the sleeve to the extent that the latter shall have the tight fit incident to forcing it into the tube by a hydraulic press. The interior of the sleeve is preferably the same diameter as the tube interior so that neither reduction of diameter that would choke the oil flow, nor diminution of wall thickness to impair strength will occur. By way of illustration with a tube having an internal diameter of three inches, the thickness of the protecting sleeve may be a third or half the thickness of the tube wall. 7

The outer end of the protecting tube preferabl is flared outwardly, as shown, to promote the free flow of oil.

What I claim is:- V V 7 An oil tube still comprising tubes and connecting headers, the'tubes being of a metal subject to alteration by action of flowing oil, and sleeves in the tube ends at the headers, of a metal that resists alteration by flowing oil, said sleeves being fixed in recesses in the walls of the tubes, and the internal diameter of the sleeves being the same as the internal diameter of the tubes in which they are placed, the tube ends extending slightly into'the header space and the sleeve ends extending beyond such tube ends, each tube being made of a single piece of metal.

SYLVESTER DAYSON. 

